Apparatus for compressing fluids



June 1950' J. 5. PARENT! 2,510,247

APPARATUS FOR COMPRESSING FLUIDS Original Filed May 19, 1942 2 Sheets-Sheet 1 )1? OR I ATTORNEYS June 6, 1950 J. s. PARENTI APPARATUS FOR COMPRESSING FLUIDS 2 Sheets-Sheet 2 Original Filed May 19, 1942- ATTORNEYS Patented June 6, 1 950 UNIT D RAT E NT." F ICE eBEAEMlW F9? Josephs. Barenti, Cleveland Ohio eml eii lk a 19. e al 9: 431666. "Divided and thisapplic tione tem referee; seaw tiiee' 3- Claims.

This invention relates to improvements in machine's of the sliding piston'or positive displacement type, which may be'used, forexa'm'ple, as compressors orpu'rniis to operate on air and other gases.

This is a division of my copendingapplication Serial'No. 443,666; filed May 19, 1942; nowPatent No. 2391,4176 of December 25 194 5. 3 one of 'the objects of this invention is to provide' an improvedmethocloi compressing gas in Wfiih e d a m r sse s e t n eit fi tsjmg member after exhaust, is added to, gas at a lower pressure which is about to 'be compressed. "It is 'also'an ohjectof' this invention to provide tran versasccr i hereof line 3:3, Eire. the part nbsineshcwn .1. .d fi rent.pcsiti nsinthe fig r E s- 4: 5.3 f a mentary. perspectiveview oivthe 9 the. c mpressor.

While, I have shown my improvements. emho ed in a rotary cylinder typeof compressor yet ijilwi l; beobvious that it is. not, intended. tolimit all ofv the improvements herein. described to the typeuofi compressor. shown in the drawings, since some, 01% the improvements shown may. be, used in,v connection with machines for other purposes thee e mpr sen ase and i machines in which the cylinders arestatio 'nary.

My improved machine maybe mounted on any suitable or desired stationary supports and may be enclosed in'a' housing or casing of any desired construction. In the particular construction iilustratedby 'way oi":- eiiample, I have provided a orenclosure 'includihg a lower part and an upper, removable part or cover 2 l, which maybe suitably secured to the main or lower housing part '20; Thejlower housing part is also provided with integrallyiormed pedestals or supports for the revolving'parts or the machine, these pedestals including" two pairs ofupright struts or flanges 22 which may be formedintegral with the housing.' A housing andsupports of any other suitable ordesired construction may be empioyed'ir desired. I

The machine shown in the drawing includes two revolving parts which rotateabout different area In the'particular construction shown, the

'cyl'inders rotate about an axis which is eccentric with'reference to a rotary member which the piston rods are connectedto, to produce relative movement btweenflhe pistons and their cylinders; provide'at each end of the machine a main stationary'bearing support 25- on which the two revolving 'elementsof the machine are journalled and whichfin turn, is mounted upon the pedestals or supports 22 Consequently, each end ofthe machine'is providedwith one of these bearing supporting members 25 which are of tuhular'formend have oppositely extending lugs or projections"arrangd to'be mounted-- on the pedestals- 22'. The hearing supporting members 25 are-each provided with an annular cylindrical portion or flange 21 within which a suitable beari-hg, such as a roller bearing 28; is arranged. Each hearing support is also provided with a cylindrical portion 2-9 of largerdiameter and eccentric with relation to the bearing flange 21. Another bearing 30 1s arranged on the periphery of the cylindricalfport ion 29. These two'fianges or cylindrical portions are connected-hiya vertical web 3 L. Strebresents an annular flange which is connected by means'ofi radially extending ribs or supporting parts'eil with fthe cylindrical flange Z9; Theseveral parts of each bearing support are preferably formed; integral, thus forming a strong and rigid bearing support which is amply capable of withstanding the reacting forces transmitted theretqby'the bearings 28 and 38.

The bearings 2 8-"of the two bearing supporting members 2 5 have then-inner races secured to rotatable hollow trunnions or shafts 3t and 31 which extend freely through the stationary bearing supporting members. The inner ends of these trunnions are suitably secured to a cylinder-carryingmember or wheel with which the cylinders are preferably formed integral and which includes a plurality of cylinders 38 connected by radially extending webs 39 and also preferably by a series of radiating and reinforcing fins to which are substantially annular in form and con centric with the axis of rotation of the cylinder wheel. The trunnions 35 and 31 may be secured to the cylinder wheel in any suitable or desired manner, and in the construction shown, the inner ends of the trunnions are provided with outwardly extending flanges ill which may be secured by bolts or other means to the cylinder wheel, see particularly Fig. 1. Consequently, the cylinder wheel is rotatably mounted on the bearings 28, and one of the hollow trunnions, for example the trunnion 36, may be provided at the outer end thereof with any suitable means for driving the cylinder wheel, a grooved pulley 42 being shown by way of example in Fig. 1.

The cylinders are provided with pistons 44 which will be hereinafter described more in detail. These pistons may be reciprocated in their cylinders in any desired manner, and in the construction illustrated by way of example, the pistons have pins 45 extending transversely through the same near the outer ends thereof. These pins 45 also extend outwardly beyond the sides of the cylinder wheel, this wheel being provided at the cylinder portions thereof with slots d6 into which the pins 35 may enter when the pistons are in their inner positions. On each end of each pin 45, one end of a piston rod or link 48 is journalled on suitable bearings 49, and the other ends of the piston rods or links 48 are pivoted on master rings which are journalled to rotate about the bearings 30, eccentrically with reference to the axis of rotation of the cylinder wheel. In the particular construction shown, these master rings are each constructed of two parts or halves and 52, secured together by means of screws 53 which also serve as pivots for the other ends of the piston rods or links. Suitable bearings 54 are arranged between the pins 53 and the inner ends of the connecting links or rods. The master rings are arranged at the opposite sides of the cylinder wheel, and since the master rings rotate about the bearings, which are eccentric with reference to the bearings 28 of the cylinder wheel, it will be obvious that at each rotation of the cylinder and master rings, the pistons 44 will be moved by their piston rods 48 through an inwardly directed working stroke and an outwardly directed intake stroke.

In order to cause the master rings and cylinder wheel to rotate about their axes simultaneously and in correct relation to each other, a suitable connection between these parts is provided. In the construction illustrated by way of example, I have provided the outer portions 52 of the eccentric master rings with a plurality of outwardly extending arms 55, four such arms being preferably employed. To the outer end of each of these arms, one end of a link 51 is pivotally connected. The other ends of these links are pivotally connected with the cylinder wheel. This may be accomplished in any desired manner, and in the construction shown, the cylinder wheel is provided between some of the cylinders with enlargements or bosses 58 in which pins 59 are arranged, the pins being preferably journalled in these bosses. The ends of the pins are secured frusto-conical to the other ends of the links 57. It will be noted that during the rotation of the master rings and the cylinder wheel, the links 51 occupy various positions, and when these master ring links are in or near a plane passing through the two axes of rotation, no driving force can be transmitted through such links, but at such times the other master ring links are not located near this plane and will transmit the necessary force for driving the master ring from the cylinder wheel, which is positively driven from the pulley 42 or other driving means. The distance between pivotal centers of the master ring links 51 must be the same as the distance between the axes of the cylinder wheel and the master ring. By means of this arrangement, the relationship between all of the cylinders and their pistons will be the same as they pass any point in their path of movement about the center of rotation of the cylinder wheel, and also the connecting rods on both sides of the cylinder wheel are kept in alinement with each other so that the resultant of the force transmitted by a pair of rods to its piston is substantially coaxial with the piston, which, in turn, results in elimination of any cocking or wedging action on the pistons and of any tendency to turn or twist the pistons about their axes.

In order to supply gas to be compressed to the cylinders and to discharge the compressed gas from the cylinders, a tubular member is provided having both an inlet passage and a discharge passage therein, the member shown including an inlet duct 60 which extends through the hollow trunnion 36 and a discharge duct 6i which extends through the hollow trunnion 37. These inlet and exhaust ducts are preferably formed integral with a valve member 62 arranged for cooperation with the cylinder wheel at the inner ends of the cylinders 38. This tubular member including the valve 62, as well as the ducts 6i] and. Si, in the particular construction shown, is stationary with reference to the cylinder wheel, and the valve member is of frusto-conical shape. The valve member is provided with a relatively large inlet port 63 which forms substantially a continuation of the inlet duct or passage 50 and a smaller exhaust or discharge port 64 which forms a continuation of the discharge duct 6|. Both of these ports are of elongated form in order to cooperate with elongated ports formed at the inner ends of each of the cylinders 38. The discharge duct 6! may, of course, be of smaller diameter than the inlet duct, and this enables the discharge duct to be spaced from the trunnions 31. This space between the duct and the trunnion resists the transmission of heat from the hot duct 6| to the trunnion bearing. If desired, suitable heat insulation may be provided in the space between this duct and the trunnion.

The middle portion of the cylinder wheel is provided with a frusto-conical bore formed for close fitting cooperation with the valve member 32, and the cylinder wheel is provided at the opposite ends of its frusto-conical bore with annular imperforate sealing surfaces 66 and 6'! which fit against corresponding surfaces 68 and 69 formed on the valve member so that when the valve is in its operative position, discharge of gases past the cooperating sealing surfaces is prevented. The cylinder wheel is provided at its valve-engaging base with an elongated port 1E1 for each cylinder. The opposite longer bounding edges of these ports 10 are arranged at an inclination to each other because qttheirust -cqnical formnit evvalv member.

so, that al portions, 0t any, longitudinal ,edge of .eilr e, ts 10.: lmult n s omeint vsubstantially fiat, seealso Figs. land-,3; Thismalges it possible-to provide arelatively large number. of cylinders in. the cylinder wheel, andrat the same time keep, the valve ,62 0t relativelysmall diameter.- The cylinders in; the: construction shown arerprovided in their cylindrical portions with cylinder sleeves l2 rigidly securedgthereto'. which maybe of a material diiie ingfrom; the material of which the cylinder wheel ismade. For example, the cylinder sleeves l2 may be of cast iron and the cylinder-wheel may, if desired, bemade of a light weight metal or-alloy;

By means of the constructionofi the-valve.- and valve ports, the ports,,because oftheirelongated shape, have the .desired crosssectionalarea-,and, at the same time, the frusto-conicalvalve mem-: her is of comparatively small-diameter, so that the lineal speed of the frusto-conical portion of the revolvingcylinder wheel-with reference to the stationary valve, is kept small enough to. avoid excessive wear of these;= centact ingsurfaces;

The,- 1stationary valve may be. maintaineddin tight seating relation'to the ,fIlJ tQ-rconicahinner portionpf. the cylinder wheel-many suitable.- or desired manner, and preferably this; is accomplishedby yieldingly urging the valvemember a'ndiitsinlet and dischargepassages in a lengthwise direction to seat the valve memberwinither base of the cylinder wheel; For exampleyin; the construction illustrated, the discharge duct 1 6 [5. of:- thelvalve member-is provided with an outwardly: extending flange l4 suitablysecured to the: dis; ch ree uct tl f r mple; y .meansofa screw-=1 threaded connection, as shown, andrthis. flange; 14 is yieldingly, urged tothealeitsin-Fig. 1,"by means; of springs '45 extending abouttboltsw-or studsiJBT; which are screwed into a stationary disk .or part H: ofrthe machine. This disk '11-, alsoiservesi-the s purpose of holding the bearing; in -place; as: clearlyshown in Fig. 1. A similar bearing.retain-' ing disk 1% is provided at the opposite-end of;the. machine which is held inplace by nuts or-studs or other suitable means,- and 'similarstudsnor: screws (not shown) may be usediorsecuring the disk l8-to the other stationary bearing shaft. 25: on Qthe discharge ,end of the machine. Con-v seguently, the springs'l5 urgethe-flange-Ji to: the left in Fig 1 and urge, the .valveinto'seating: engagement in thebore of, the cylin'derwwheel. Nuts 80, are adjustably-mounted on the, studs T61 topermit varying the pressure. with which: the

valve is urged into seating engagement with the bore of the cylinder wheel, so that thepressure of the springs can be varied, depending upon the pressure of the fluid discharged fromthe' cylin-- ders.

The valve construction described is desirable for thereason that the springs automatically :compepsate. forwear of themvalveior ofithe metalatthe;-,bore of the pylinderiwheeh The: flange 1'4 and the studs 1 61; may alsoab usediito; hold the tubular member: and thevalve against? turning with the cylinder wheel. For this purpose, the flange 74 may be provided with slots 8;l. ,.Eig.:, 1;. into which. the ends of the? studs extend. Sincelduring the rotationeof the cylinder-wheel; these-studs willibear against one siclezonly; of; the slots, the studs: are preferably pitovicledzwith'flat sides which bear against. those sides: of the slots, with which. theywill engage during-1,. the: rotation. ofthe cylinder wheel, and the vslotsare also.formedso that each side=against whichialstudl bearslies substantially ina radial plane. extending. through the centerof rotation of: the icylinderfwheela Consequentlmthe' studs 16 oppose 'iorce tending to turn theflang'e- M withoutiproducing radial components of this forte,

' Tliewslots. 81 are also made long enough and wide enoughto permit any slight movement that may beimparted to the d'ischarge duct- 6| because' of inac'curacies in machining. I

83 represents :a pipe or tube'which conducts the oompressed g-as from the 1 dischargeduct 5 I; and which-' in the construction shown h'a's-"aflalng which-issecuredto the flange 14. This tube- 83; is ipreferablyfie'xible'to-allow= for any slight move-- menwofjthe duot- 6|.

In the operation" of the compressor thusrar de'scribed;- when power is applied 'to-rotate"thei trunnion 35;"th'e cylinder wheel rotates 'about its axis.- Through the medium of the master ring links 51', rotary *motion is imparted from" the cylinder wheelto the eccentric master rings ar: ranged at-opp0sitesides of the cylinder wheel and mounted-= on the bearings 30-,whichare ec-- centric with-relationto theaxis of rotation of the cylinder wheeli Consequently-the pistons will be caused to reciprocate in-their cylinders; In the machine illustratedinthe drawings; the axis oi'rotation of the cylinder-wheel is 'located ver' tic'all y above-the axis of rotation of the master ring, and consequently-when a cylinder-reaches? approximately the upper portion of'themachine; its pis'ton will' be in its inner position; Assuming; that rotation is in a clockwise direction in Figs; 2,: 3-and-'4;each piston, as it"moves with the cylinder-wheelfrom the upper position; will move" outwardly; and will move into communication" with theinletport 63 of the valve member. When. it reaches thelower portion "of its 'movemenii'th'e'. piston-willb its outermost position, and from" then: onto its upper position, it will be moved inwardly in its cylinder to compress the gas taken? in. During a part of 'thetime :that a cylinder-i passes through the upper, left quadrantin Figs. 2; 3 and i its' port moves" into 'reg istra'tionwith" the dis'charge-port 66 of the stationary valve; thus discharging the compressedgas into thedischarge duct 6|;

In compressors *as now' commonly constructed, the residuar compressed which remains in a cylinder after the closing of the discharge'va'lve,

the intake strok'ei Inacoordancewith my invention,I provide an improved method and means whereby this res'i'd-' ualgas is discharged-into a clyinder in'whi'ch the piston has just oompletedits inta'l;e,. and in which th'*=intak'e :valvefds closed; This. residual gas, .T 10 consequently, supercharges cylinder which it is discharged, so that this cylinder will compress not only the charge of gas taken in during the suction or intake stroke, but also such residual gas as is delivered to it.

Any suitable or desired means may be employed for carrying out my method. In the machine shown, this method can readily be carried out by providing a single relatively small passage through the valve 52, for example, such as the passage 90, shown in Figs. 2 to 5. It will be noted that this passage, which in the construction shown may be in the form of a hole drilled in the valve 62, is so arranged that any cylinder after its port passes out of registration with the discharge port 64 of the valve, will momentarily pass into registration with one end of the passage 90. The other end of this passage will be in registration with the port of another cylinder just after the port of such cylinder has moved out of registration with the inlet port 63. In Figs. 2 and 3, the upper cylinder is shown in the position in which it has just passed out of registration with the discharge port 64 of the valve and the lowest cylinder has just passed out of registration with the inlet port 63, and neither of these cylinders has as yet passed into communication with the connecting passage 91?. Fig. 4 shows the positions of the cylinders after they have passed through a small are beyond the positions shown in Figs. 2 and 3, and shows the upper cylinder in registration with the upper end of the passage 90 and the lowest cylinder also in registration with the lower end of this passage. Consequently, residual compressed gas in the upper cylinder will quickly flow through the passage 90 and will, consequently, be expanded during this passage, and the greater portion of this residual charge will be added to the charge of gas in the lowest cylinder, thus increasing the pressure and the quantity of gas in the lowest cylinder and also greatly reducing the amount of residual gas in the uppermost cylinder, so that when the port of this cylinder moves into communication with the inlet port 63 of the valve 52, it will take in a materially larger charge of gas than would be the case if it were first necessary to expand all of the residual compressed gas remaining in the cylinder after exhaust. Consequently, by use of the supercharge passage, the capacity of the compressor is increased, in the first place, because of the fact that with very little residual gas in the uppermost cylinder, this cylinder will take on a proportionately larger charge of fresh gas during its intake stroke. The capacity of the machine is further increased by the fact that the cylinder receiving the residual charge is supercharged and, consequently, compresses a proportionately greater amount of gas than would be the case if it had not been thus supercharged. Any other means for transferring residual compressed gas from a cylinder to supercharge a quantity of gas to be compressed may be provided.

Not only does my improved method greatly increase the capacity of any compressor to which it is pplied, but also the efficiency of the comp'ressor is greatly increased thereby. For example, the residual compressed gas which is added to the gas which is about to be compressed raises the pressure of this latter gas without requiring any additional work by the compressor. It is, consequently, also possible to make the intake port 63 larger, so that the intake port of each cylinder may be in communication therewith for a longer period of time, without having the residualcompressed gas discharged into the intake passage, which would cause objectionable tur-= pressure in the cylinders is slightly below atmospheric, and since a number of cylinders are always in communication with the intake port,

there will be a constant and steady now of air in the inlet duct.

A further advantage of the removal of residual gas from a cylinder and employing it to supercharge an intake of gas, is that this enables compressors to compress gases to much higher pressures than has heretofore been possible in a single stage. Heretofore, the pressures which could be produced in a single stage were limited by the clearance between the cylinder heads and the pistons, or in other words, by the amount of residual compressed gas left in a cylinder. If the pressure in a cylinder reached a certain point at which the residual required the full stroke of the piston to become re-expanded, obviously no additional gas could be taken in and, consequently, no compressed gas would be delivered. Consequently, heretofore, the maximum pressure in any cylinder had a definite limitation because of the expansion of the residual compressed gas. By means of my method and construction, since most of the residual gas is discharged from the cylinder, it follows that only a very slight movement of the piston in the cylinder will expand the very small quantity of residual gas left in the cylinder after su'percharging, and consequently, the maximum gas pressure that can be delivered by any cylinder is greatly increased.

I claim as my invention:

1. A multi cylinder compressor, comprising a pair of cylinders arranged in fixed relation to each other and having pistons therein, means connecting said pistons for reciprocating the same in said cylinders so that the pistons simultaneously occupy opposite positions of their strokes, a valve having inlet and discharge passages for communicating with said cylinders, said valve having a passage therein connecting said cylinders immediately after communication of said cylinders with said valve passages has been interrupted to discharge residual compressed gas from a cylinder whose discharge of compressed gas to said discharge passage has just been completed, into a cylinder whose intake of gas has just been completed.

2. A multi cylinder compressor having a member rotatable about an axis and having a plurality of cylinders formed integral therewith and arranged in pairs, the cylinders of each pair being located diametrically opposite each other on said member, means for imparting rotation to said member, said member having an axial bore and each of said cylinders having a port terminating in said bore for intake and discharge of gas, pistons in said cylinders, means for reciprocating said pistons in said cylinders during the rotation of said member and cylinders, said means being so constructed that the pistons in each of said pairs of cylinders will be simultaneously at opposite ends of their strokes, a central stationary valve arranged within the bore of said member and having inlet and discharge passages with which said ports of said cylinders communicate during their rotation, and an additional passage in said valve member arranged to connect a pair of oppositely disposed cylinders, said additional passage being so located in said valve member as to simultaneously communicate with the port of one cylinder of a pair immediately after its port has passed out of communication with the discharge passage of said valve, and with the port of the opposite cylinder immediately after it has passed out of communication with the inlet passage of said valve, whereby compressed gas in said first mentioned cylinder superchargcs the other cylinder of the pair.

3. In a rotary cylinder compressor having a plurality of cylinders arranged substantially radially with reference to the axis of rotation of said rotary cylinders and in fixed relation to each other, said cylinders being arranged in substantially diametrically oppositely located pairs, means for rotating said cylinders, pistons operating in said cylinders, means for reciprocating said piston in said cylinders so that the pistons in opposite pairs of cylinders are arranged at opposite positions in their strokes, a stationary valve member arranged substantially coaxial with the axis of rotation of said cylinders and having inlet and discharge passages, said cylinders each having a port arranged to cooperate with the passages of said valve member, and a third passage extending crosswise of said valve member and having one end thereof arranged to connect 10 with the port of a cylinder which has just passed out of communication with said discharge passage and having the other end arranged to simultaneously connect with the port of a cylinder which has just passed out of communication with said inlet passage, for supercharging one cylinder with residual compressed gas of the other cylinder.

JOSEPH S. PARENTI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 741,419 Sutton Oct. 13, 1903 904,219 Patrick Nov. 17, 1908 941,646 Olsen et a1 Nov. 30, 1909 1,000,539 Nauer Aug. 15, 1911 1,272,611 Braley July 16, 1918 1,582,264 Gribojedofi Apr. 27, 1926 2,073,710 Rayfield Mar. 16, 1937 2,150,347 Sorensen Mar. 14, 1939 2,391,476 Parenti Dec. 25, 1945 

